Flashcard 13 - Subtest II: Mathematics Flashcard Set for the CSET Multiple Subjects Test

180 ft

Let x be the width and 2x be the length. Their product, lw, will be the area.

\(A=lw\)
\(A= 2x \cdot x\)
\(A= 2x^{2}\)
Substitute \(1800\ ft^{2}\) for A and solve for x.
\(2x^{2}=1800\ ft^{2}\)
\(x^{2}=900\ ft^{2}\)
\(x=30\ ft=w\)
If \(w = 30\), then \(l = 60\), and the perimeter is \(2\cdot30+2\cdot60=180\ ft\).